faiss/IndexShards.h

101 lines
3.3 KiB
C++

/**
* Copyright (c) Facebook, Inc. and its affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*/
#pragma once
#include "Index.h"
#include "IndexBinary.h"
#include "ThreadedIndex.h"
namespace faiss {
/**
* Index that concatenates the results from several sub-indexes
*/
template <typename IndexT>
struct IndexShardsTemplate : public ThreadedIndex<IndexT> {
using idx_t = typename IndexT::idx_t;
using component_t = typename IndexT::component_t;
using distance_t = typename IndexT::distance_t;
/**
* The dimension that all sub-indices must share will be the dimension of the
* first sub-index added
*
* @param threaded do we use one thread per sub_index or do
* queries sequentially?
* @param successive_ids should we shift the returned ids by
* the size of each sub-index or return them
* as they are?
*/
explicit IndexShardsTemplate(bool threaded = false,
bool successive_ids = true);
/**
* @param threaded do we use one thread per sub_index or do
* queries sequentially?
* @param successive_ids should we shift the returned ids by
* the size of each sub-index or return them
* as they are?
*/
explicit IndexShardsTemplate(idx_t d,
bool threaded = false,
bool successive_ids = true);
/// int version due to the implicit bool conversion ambiguity of int as
/// dimension
explicit IndexShardsTemplate(int d,
bool threaded = false,
bool successive_ids = true);
/// Alias for addIndex()
void add_shard(IndexT* index) { this->addIndex(index); }
/// Alias for removeIndex()
void remove_shard(IndexT* index) { this->removeIndex(index); }
/// supported only for sub-indices that implement add_with_ids
void add(idx_t n, const component_t* x) override;
/**
* Cases (successive_ids, xids):
* - true, non-NULL ERROR: it makes no sense to pass in ids and
* request them to be shifted
* - true, NULL OK, but should be called only once (calls add()
* on sub-indexes).
* - false, non-NULL OK: will call add_with_ids with passed in xids
* distributed evenly over shards
* - false, NULL OK: will call add_with_ids on each sub-index,
* starting at ntotal
*/
void add_with_ids(idx_t n, const component_t* x, const idx_t* xids) override;
void search(idx_t n, const component_t* x, idx_t k,
distance_t* distances, idx_t* labels) const override;
void train(idx_t n, const component_t* x) override;
// update metric_type and ntotal. Call if you changes something in
// the shard indexes.
void sync_with_shard_indexes();
bool successive_ids;
protected:
/// Called just after an index is added
void onAfterAddIndex(IndexT* index) override;
/// Called just after an index is removed
void onAfterRemoveIndex(IndexT* index) override;
};
using IndexShards = IndexShardsTemplate<Index>;
using IndexBinaryShards = IndexShardsTemplate<IndexBinary>;
} // namespace faiss